AUGUSTA, Maine — A Michigan corrections official has been appointed warden of the Maine State Prison in Warren.

Patricia Barnhart, acting warden of the Thumb Correctional Facility in Lapeer, Mich., is expected to take over as warden in the high-security Maine prison in early December. She will become the first female warden of an all-male prison facility in Maine.

Barnhart succeeds Warden Jeff Merrill, who will lead the state Corrections Department’s energy conservation efforts. Corrections Commissioner Marty Magnusson says Barnhart has more than 20 years of experience in corrections and will bring progressive leadership to prison. Maine State Prison has a capacity for 916 prisoners.